backup-mail-and-secrets

#!/bin/bash
function exit_error(){
    case "$1" in
        0)
            notify-send 'Backup Script Failed' 'Reason: Internet is down'
            ;;
        1)
            notify-send 'Backup Script Failed' 'Reason: Error archiving folder(s)/file(s)'
            ;;
        2)
            notify-send 'Backup Script Failed' 'Reason: Error encrypting file(s)'
            ;;
        3)
            notify-send 'Backup Script Failed' 'Reason: Error copying file to myserver.com'
            ;;
        4)
            notify-send 'Backup Script Failed' 'Reason: md5sum mismatch'
            ;;
    esac
    exit
}

function set_vars(){
    case "$1" in
        0)
            remote_mail_sha512="$(ssh user@myserver.com 'sha512sum /home/admin/web/myserver.com/public_html/mail.tar.gz.gpg' | grep -oe '[0-9a-f]\{128\}')"
            local_mail_sha512="$(sha512sum '/home/user/mail.tar.gz.gpg' | grep -oe '[0-9a-f]\{128\}')"
            export remote_mail_sha512 local_mail_sha512
            ;;
        1)
            remote_kdbx_sha512="$(ssh user@myserver.com 'sha512sum /home/admin/web/myserver.com/public_html/mpw.kdbx' | grep -oe '[0-9a-f]\{128\}')"
            local_kdbx_sha512="$(sha512sum '/home/user/Documents/mpw.kdbx' | grep -oe '[0-9a-f]\{128\}')"
            export remote_kdbx_sha512 local_kdbx_sha512
            ;;
    esac
}

sleep 15
set_display_preferences
ping 1.1.1.1 -c1 -w1 || exit_error 0
mail_modified='false'

for mailbox in /home/user/Mail/*; do
    [[ "$mailbox" -nt '/home/user/mail-last-modified' ]] && mail_modified='true'
done

phone_id="$(kdeconnect-cli -l | grep 'Sony.*paired and reachable' | grep -oe '[0-9a-f]\{16\}')"
set_vars 0
if "$mail_modified" || [[ "$local_mail_sha512" != "$remote_mail_sha512" ]]; then
    touch '/home/user/mail-last-modified'

    tar czf '/home/user/mail.tar.gz' '/home/user/Mail' || exit_error 1
    gpg --batch --yes --output '/home/user/mail.tar.gz.gpg' --encrypt --recipient user@mydomain.com '/home/user/mail.tar.gz' || exit_error 2
    rm -f '/home/user/mail.tar.gz'
    scp '/home/user/mail.tar.gz.gpg' 'user@mydomain.com:/home/admin/web/mydomain.com/public_html/' || exit_error 3

    set_vars 0
    [[ "$local_mail_sha512" == "$remote_mail_sha512" ]] || exit_error 4

    [[ -z "$phone_id" ]] || cp '/home/user/mail.tar.gz.gpg' "/run/user/1000/${phone_id}/storage/emulated/0/Download/mail.tar.gz.gpg"

    uploaded_files=('mail.tar.gz.gpg')
fi

set_vars 1
if [[ "$local_kdbx_sha512" != "$remote_kdbx_sha512" ]]; then
    scp '/home/user/Documents/mpw.kdbx' 'user@mydomain.com:/home/admin/web/mydomain.com/public_html/' || exit_error 3

    set_vars 1
    [[ "$local_kdbx_sha512" == "$remote_kdbx_sha512" ]] || exit_error 4

    [[ -z "$phone_id" ]] || cp '/home/user/Documents/mpw.kdbx' "/run/user/1000/${phone_id}/storage/emulated/0/Download/mpw.kdbx"

    uploaded_files+=('mpw.kdbx')
fi

if [[ ! -z "${uploaded_files[*]}" ]]; then
    file_list="${uploaded_files[*]}"
    notify-send 'Backup Script Successful' "Successfully uploaded:\\n${file_list// /$'\n'}"
    [[ -z "$phone_id" ]] || kdeconnect-cli -d "$phone_id" --ping-msg "Received files: ${file_list// /, }"
else
    notify-send 'Backup Script Successful' 'No uploads were needed'
fi